The present invention relates in general to an apparatus for forming shock-absorbing members of synthetic material inside a container, and more particularly, to an automatic system for forming shock-absorbing members of synthetic foamed material into predetermined shapes at pre-selected locations inside a container for the cushioning of an article to be provided therein.
As is known to those skilled in the art, the preparation of many synthetic foamed materials, such as polyurethane foamed material, requires uniform mixing of liquid organic resins with polyisocyanates in a so-called mixing chamber of a dispensing apparatus. One such dispensing apparatus for the discharging of synthetic foamed material is disclosed in U.S. patent application Ser. No. 298,456, filed on Sept. 2, 1981 and assigned to the same assignee of the present invention, which dispensing apparatus is incorporated by reference herein. In regard to such dispensing apparatus, it has been considered desirable, but never commercially feasible, to incorporate the dispensing apparatus into an automatic system for forming shock-absorbing members of such polyurethane foamed material into predetermined shapes at pre-selected locations inside a container for the cushioning of an article to be provided therein during a packaging operation.
In accordance with one known prior art apparatus, there is known a mold assembly for manually forming shock-absorbing members of polyurethane material into predetermined shapes at pre-selected locations inside a packaging container. Specifically, the mold assembly includes a male mold for forming the polyurethane material into such shapes at such locations within the container. The container, having an open top and bottom, is placed over the mold and secured to the mold assembly by engagement with the container's end flaps. A process operator manually dispenses the polyurethane foam from a single hand-held dispensing apparatus into the container through its open bottom in order to surround the mold and fill the voids formed between the mold and the walls of the container. Once the container has been filled to approximately three-quarters of its capacity with the polyurethane foam, the process operator terminates the dispensing operation. At such time, the process operator closes the end and side flaps along the bottom of the container while allowing the polyurethane foam to expand upwardly into the unfilled voids. After the polyurethane foam has completely expanded, the process operator seals the bottom of the box and removes it from the mold assembly.
In application of the prior art mold assembly by the process operator in a manual operation, a number of disadvantages result therefrom. Specifically, the process operator often overfills the container with polyurethane foam causing such foam during its expansion to either rupture the container walls or to cause partial collapse of the foam due to its restricted confinement within the container. In either event, the partial collapse of the polyurethane foam or rupturing of the container renders the formed shock-absorbing members and container unsuitable for use, along with the associated economic loss. In addition, the polyurethane foam, under such circumstances, often spills onto and fouls the mold assembly requiring that it be thoroughly cleaned before continued use. The process operator is further found to often cause spilling of the polyurethane foam on the outside of the container itself which renders such container unsuitable for customer use and on the floor which requires a further time-consuming and costly clean-up operation. Further still, it has been found that the process operator often drops the dispensing apparatus when closing and sealing the bottom of the container such that the dispensing apparatus is often damaged. In addition, the continued movement of the heated organic resin and polyisocyanate supply lines often results in high maintenance and frequent replacement thereof as such movement and flexing causes their ultimate cracking or rupturing during continued use.
Accordingly, it can be appreciated that there is an unsolved need for an automatic foam dispensing system for forming shock-absorbing members of synthetic foamed material into predetermined shapes at pre-selected locations inside a container for the cushioning of an article to be provided therein in such a manner so as to remove the dispensing apparatus from the hands of the process operator.